#include <iostream>
#include <vector>
long long N, // Number of spots - 1
Q, // Number of tectonic movements
S, // Temperature decrease per altitude if it increases
T; // Temperature increase per altitude if it decreases
long long calc(long long diff) {
return diff > 0 ? -S * diff : -T * diff;
}
int main() {
std::cin >> N >> Q >> S >> T;
std::vector<long long> A(N + 1); // Initial altitudes
std::vector<long long> L(Q), R(Q), X(Q); // Spot L to R's altitude is changed by X in tectonic movement Q
std::vector<long long> diff(N + 1);
for (long long i = 0; i < N + 1; i++) {
std::cin >> A[i];
if (i != 0) {
diff[i] = A[i] - A[i - 1];
}
}
for (long long j = 0; j < Q; j++) {
std::cin >> L[j] >> R[j] >> X[j];
}
long long result = 0;
for (long long i = 1; i <= N; i++) {
result += calc(diff[i]);
}
for (long long j = 0; j < Q; j++) {
result -= calc(diff[L[j]]);
diff[L[j]] += X[j];
result += calc(diff[L[j]]);
if (R[j] != N) {
result -= calc(diff[R[j] + 1]);
diff[R[j] + 1] -= X[j];
result += calc(diff[R[j] + 1]);
}
std::cout << result << std::endl;
}
}
